Nomad changes

docs/snippets/php/metadata/pdf_metadata_extractor.php

@@ -0,0 +1,114 @@
+```php title="pdf_metadata_extractor.php"
+<?php
+
+declare(strict_types=1);
+
+/**
+ * PDF Metadata Extractor Post-Processor
+ *
+ * Custom post-processor that extracts and enriches PDF metadata
+ * during the extraction pipeline.
+ */
+
+require_once __DIR__ . '/vendor/autoload.php';
+
+use Kreuzberg\PostProcessor\PostProcessorInterface;
+use Kreuzberg\Types\ExtractionResult;
+use Kreuzberg\Kreuzberg;
+
+/**
+ * Post-processor for extracting and enriching PDF metadata
+ */
+readonly class PdfMetadataExtractor implements PostProcessorInterface
+{
+    private int $processedCount;
+
+    public function __construct()
+    {
+        $this->processedCount = 0;
+    }
+
+    /**
+     * Get the name of this post-processor
+     */
+    public function name(): string
+    {
+        return 'pdf_metadata_extractor';
+    }
+
+    /**
+     * Get the version of this post-processor
+     */
+    public function version(): string
+    {
+        return '1.0.0';
+    }
+
+    /**
+     * Get the description of this post-processor
+     */
+    public function description(): string
+    {
+        return 'Extracts and enriches PDF metadata';
+    }
+
+    /**
+     * Get the processing stage (early, normal, or late)
+     */
+    public function processingStage(): string
+    {
+        return 'early';
+    }
+
+    /**
+     * Determine if this processor should handle the result
+     */
+    public function shouldProcess(ExtractionResult $result): bool
+    {
+        return $result->mimeType === 'application/pdf';
+    }
+
+    /**
+     * Process the extraction result
+     */
+    public function process(ExtractionResult $result): ExtractionResult
+    {
+        $this->processedCount++;
+
+        if (!isset($result->metadata->custom)) {
+            $result->metadata->custom = [];
+        }
+        $result->metadata->custom['pdf_processed'] = true;
+        $result->metadata->custom['processor_version'] = $this->version();
+
+        return $result;
+    }
+
+    /**
+     * Initialize the post-processor
+     */
+    public function initialize(): void
+    {
+        error_log("PDF metadata extractor initialized");
+    }
+
+    /**
+     * Shutdown the post-processor
+     */
+    public function shutdown(): void
+    {
+        error_log("Processed {$this->processedCount} PDFs");
+    }
+
+    /**
+     * Get the number of processed documents
+     */
+    public function getProcessedCount(): int
+    {
+        return $this->processedCount;
+    }
+}
+
+$processor = new PdfMetadataExtractor();
+Kreuzberg::registerPostProcessor($processor);
+```